Time-Variations of 17GHz Radio Bursts with Multi-Source Structures

Four multi-source radio bursts observed with the new 17GHz interferometer at Nobeyama are analyzed and presented from the point of view of their time-variations.Three of them (Sep. 6, 1978; Oct. 9, 1978; and Feb. 17, 1979) were essentially of an impulsive nature and all showed distinct double-source structures. Their polarization structures and time-variations are discussed and compared with type III and type II burst occurrences. The results of the comparison suggest either that electron accelerating regions moved across magnetic lines of force or that a rapid magnetic field rearrangement occurred near an accelerating region.A quite different type of multi-source radio bursts was observed on Nov.10,1978. It had a long duration of several hours and was associated with type IV bursts at metric and decimetric wavelengths. At least five radio sources were observed to appear at 17GHz. A detailed description of this event is presented in comparison with the evolution of both Hα-flare and type IV bursts.

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Type II Solar Radio Bursts over Solar Cycle 21

International Astronomical Union Colloquium ◽

10.1017/s025292110002546x ◽

1994 ◽

Vol 144 ◽

pp. 283-284

Author(s):

G. Maris ◽

E. Tifrea

Keyword(s):

Solar Radio ◽

Interplanetary Space ◽

Impulsive Phase ◽

Radio Bursts ◽

Type Ii ◽

Solar Radio Bursts ◽

Strong Energy ◽

Mass Ejection ◽

Geophysical Effect ◽

Radio Event

The type II solar radio bursts produced by a shock wave passing through the solar corona are one of the most frequently studied solar activity phenomena. The scientific interest in this type of phenomenon is due to the fact that the presence of this radio event in a solar flare is an almost certain indicator of a future geophysical effect. The origin of the shock waves which produce these bursts is not at all simple; besides the shocks which are generated as a result of a strong energy release during the impulsive phase of a flare, there are also the shocks generated by a coronal mass ejection or the shocks which appear in the interplanetary space due to the supplementary acceleration of the solar particles.

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Saturn's E, G and F rings: modulated by the plasma sheet

International Astronomical Union Colloquium ◽

10.1017/s0252921100101666 ◽

1984 ◽

Vol 75 ◽

pp. 597

Author(s):

E. Grün ◽

G.E. Morfill ◽

T.V. Johnson ◽

G.H. Schwehm

Keyword(s):

Solar Wind ◽

Direct Contact ◽

Transport Processes ◽

Time Variable ◽

Dust Particles ◽

Spatial Diffusion ◽

Drag Forces ◽

Orbit Perturbation ◽

Time Variations ◽

F Ring

ABSTRACTSaturn's broad E ring, the narrow G ring and the structured and apparently time variable F ring(s), contain many micron and sub-micron sized particles, which make up the “visible” component. These rings (or ring systems) are in direct contact with magnetospheric plasma. Fluctuations in the plasma density and/or mean energy, due to magnetospheric and solar wind processes, may induce stochastic charge variations on the dust particles, which in turn lead to an orbit perturbation and spatial diffusion. It is suggested that the extent of the E ring and the braided, kinky structure of certain portions of the F rings as well as possible time variations are a result of plasma induced electromagnetic perturbations and drag forces. The G ring, in this scenario, requires some form of shepherding and should be akin to the F ring in structure. Sputtering of micron-sized dust particles in the E ring by magnetospheric ions yields lifetimes of 102to 104years. This effect as well as the plasma induced transport processes require an active source for the E ring, probably Enceladus.

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Bevy of mysterious fast radio bursts spotted by Canadian telescope

Nature ◽

10.1038/d41586-019-00049-5 ◽

2019 ◽

Author(s):

Alexandra Witze

Keyword(s):

Radio Bursts

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Long-sought signal deepens mystery of fast radio bursts

Nature ◽

10.1038/nature.2016.20993 ◽

2016 ◽

Author(s):

Elizabeth Gibney

Keyword(s):

Radio Bursts

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Weak radio bursts in our galaxy

The New Scientist ◽

10.1016/s0262-4079(20)32030-3 ◽

2020 ◽

Vol 248 (3309) ◽

pp. 18

Author(s):

Jonathan O'Callaghan

Keyword(s):

Radio Bursts

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Innovation of Natural Preservation of Mackerel (Rastrelliger kanagurta) Using Coconut Coconut Ashes with Drying Time Variations on Hedonics

Serambi Journal of Agricultural Technology ◽

10.32672/sjat.v2i2.2433 ◽

2020 ◽

Vol 2 (2) ◽

Author(s):

Rika Agustina ◽

Rita Sunartaty ◽

Teuku Makmur

Keyword(s):

Research Design ◽

Block Design ◽

Drying Time ◽

Basic Ingredient ◽

Randomized Block Design ◽

Salt Substitute ◽

Long Time ◽

Time Variations ◽

Rastrelliger Kanagurta

Coconut frond ash is one of the wastes from coconut trees which has not been maximally utilized. Coconut frond ash contains MgCl2 and KCl so that it can be used as a salt substitute in the process of preserving fish. In this study coconut frond ash was used as a basic ingredient for making dried mackerel with a long time of drying to storage. The purpose of this study was to determine the effect of drying time on mackerel storage. The research design used was a Randomized Block Design (RCBD) with 2 factors studied. The first factor is the drying time consists of 3 levels, namely P1 = 3 days, P2 = 4 days, P3 = 5 days. The second factor is storage which consists of 3 levels, namely S1 = 30 days, S2 = 60 days, S3 = 90 days. Each treatment was repeated 2 times to obtain 18 experimental units to observed hedonic tests. From the results of the study it can be stated that the treatment has a very significant effect (P≥0.01) on the hedonic test which includes (color, aroma, taste and texture).

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